Online communication systems may allow users to communicate through messaging across different devices. Types of online communication systems may include electronic mail, instant messaging systems, blog posting systems, electronic message forums and virtual conferencing systems.
Electronic mail, or email, includes the transmission of message of a communication network. An electronic mail system, or email system, may be a system capable of sending, receiving, and storing email messages in user email mailboxes, or inboxes. Additionally, email systems may be accessible from devices, such as desktops and laptops, and mobile devices, such as smartphones and tablets. Typical email messages may be produced by entering text via a keyboard and may include electronic files stored as attachments. Furthermore, email systems may use protocols, such as simple message transfer protocol (SMTP), Post Office Protocol 3 (POP3), and Internet Message Access Protocol (IMAP), to transfer email messages between computers processing various types of software and across different servers. SMTP may be a protocol used to send email messages. POP3 and IMAP may be protocols to receive email messages.